1. Field of Invention
The present invention relates broadly to intravenous catheters to accommodate fluid flow into and out of the body cavities of patients and more particularly to a novel inside-the-needle apparatus for and method of placement of a soft sterile plastic cannula or catheter tube into the vein of a patient and reliable placement of a female adapter on the exposed end of the catheter prior to infusion.
2. Prior Art
Heretofore, various attempts to introduce a plastic cannula into the vein of a patient have been made. In some instances, a plastic cannula has been disposed on the outside of an insertion needle and the tube placed in the vein together. The needle is thereafter withdrawn leaving the catheter in the vein. However, the length of the plastic cannula that can be employed with this arrangement is limited to the length of the needle. In other instances, a plastic cannula has been telescopically inserted into the vein through the hollow of a needle following venipuncture. Thereafter, the needle is removed from the vein and the cannula retained therein to accommodate fluid flow. Removal of the needle "from the arm" at the trailing end of the cannula has presented certain problems. Slotted needles have sometimes been employed, the slot being wide enough so that the needle may be laterally separated from around the cannula after being withdrawn from the vein. Split needles which can be separated into two pieces and thereby removed from the cannula have also been proposed. Unslotted needles have been used and allowed to remain "on the arm" surrounding that portion of the cannula exposed outside the vein. This has created a problem of either immobilizing the patient or protecting the needle so that the patient is not injured by the needle. Typically, a needle protector has been snapped or otherwise placed about the sharpened leading tip of such a needle and the protector or cover guard thereafter secured to the arm of the patient by adhesive or the like.
Another concern which has faced the medical profession in regard to the foregoing is the maintenance of sterility of the catheter after it is removed from its package and prior to placement and use in the arm of the patient.
It has been proposed to retract and entirely remove the needle and any insertion device from the catheter tube of an inside-the-needle placement set and thereafter attach a female adapter to the trailing end of the catheter tube to accommodate infusion. Problems have resulted in so attaching the adapter to said trailing catheter end.
Furthermore, other problems have been encountered in turning certain adapter-receiving reinforced ends of catheter tubes to remove such from Tuohy caudal needles and thereafter placing the adpater on said catheter end.